Concrete cylinder capper

ABSTRACT

A concrete capper used in preparing a concrete test sample comprising a jiglike device for insuring the formation of a substantially planar end on the prepared sample. The jig includes a removable glass plate which permits a user to simply replace the glass plate when necessary at a small expense.

United States Patent Inventor John V. Cooke New Orleans, La.

Appl. No. 794,656

Filed Jan. 28, 1969 Patented Mar. 23, 1971 Assignee Cecil M. Shilstoneand Associates, Inc.

' a fractional part interest to each CONCRETE CYLINDER CAPPER 5 Claims,5 Drawing Figs.

(1.8. CI 25/ l 18, 249/ 8 3 Int. Cl B28!) 7/00 Field of Search 249/83,

(Test Sample Digest); 25/118 (M) [56] References Cited UNITED STATESPATENTS v 1,665,445 4/1928 Conrad 249/ 83X 2,648,888 8/ l 953 Walton249/83X Primary Examiner-J. Spencer Overholser Attorneys-Clarence A.OBrien and Harvey B. Jacobson ABSTRACT: A concrete capper used inpreparing a concrete test sample comprising a jiglike device forinsuring the formation of a substantially planar end on the preparedsample. The jig includes a removable glass plate which permits a user tosimply replace the glass plate when necessary at a small expense.

PATENTED MR2 3 um Fig.3

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John V Cooke CtM llCiilE'llh CYlLllhliiEh CAilPlElit The presentinvention relates to concrete cylinder cappers which are employed inpreparing structural test samples of cured concrete.

Due of the methods of establishing quality and structural strength ofconcrete is by testing samples taken from representative batches ofconcrete being delivered to a project. The testing procedure consists ofcasting test specimens in fiber or metal molds, curing the specimens inaccordance with standardized specifications, and testing the specimensin compression at a predetermined time after the initial casting.Standardized test procedure specifications are furnished by suchorganizations as the American Society for Testing and Materiais and theNational Bureau of Standards. The results of compressive tests performedupon the cured samples establish the compressive strength of theconcrete which is used to determinewhether or not the concrete utilizedin a particular project complies with statutory requirements or criteriaset forth by design engineers.

During conventional capping of concrete test specimens, concrete testcylinders of freshly poured concrete are molded in cylindrical iiber orsteel molds. After approximately 24 hours, the hardened concrete isremoved from the mold and stored in a temperatureand humidity-controlledcuring room until time for testing (generally between 7 and 28 daysafter molding).

Frior to testing, the concrete cylinder is capped on both ends with acapping material that will develop a compressive strength greater thanthe anticipated strength of the concrete cylinder to be tested. Thecapping of the cylinder is accomplished with the aid of the presetconcrete cylinder capper. Cylinder cappers, or capping plates in usetoday, are fabricated from refactory materials and steel which ismachined to specific tolerances for planeness of the capping surfaces.These cappers are prone to pitting and scratching which destroys theusefulness of the capping plate. in the case of steel plates, the platesbecome pitted or warped which requires expensive machining periodicallyto bring the plate within the required dimensional tolerances.

The purpose of the present invention is to provide a simple jiglikeconcrete cylinder capper which employs an easily removable capping platein the form of a glass plate. When the glass plate becomes scratched orcracked due to repeated and prolonged contact with abrasive concretematerial, the glass plate may be easily replaced at small expense.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming-a part hereof, whereinlike numerals refer to like parts throughout, and in which:

lFiG. ii is a perspective view illustrating the concrete cylinder capperof the present invention as employed to support a concrete cylinder.

PEG. 2 is a top plan view of the capper illustrated in FIG. i.

hit 3 is a longitudinal sectional view taken along a plane passingthrough section line 3-3 of H6. 2.

hi6. i is a longitudinal sectional view taken along a plane passingthrough section line M of Fit]. 2.

Fifi. 5 is a perspective view illustrating a glass plate which isemployed as a capping plate when properly inserted in the concretecylinder capper shown in HG. 1.

Referring to the drawings and more particularly FlG. l thereof, therewill be seen a jiglike concrete cylinder capper generally indicated byreference numeral iii which is employed to support a conventionalconcrete cylinder R2 in such a manner as to form a substantially planarclosure or capper at one end thereof, the capper being substantiallyperpendicular to the axis of the cylinder. The capper device i iincludes a square base plate it having countersunk boreholes to in thefour comers of the plate permitting. the base plate to be suitablymounted to a tabletop or like surface. A square glass plate i8 isutilized to cap the lower end of the concrete cylinder 12. The glassplate is characterized by a substantially uniform thickness dimensionwhich will result in the formation of a planar cap surface at the lowerend of the concrete cylinder l2. Two elongated barlike spacers 20 aredisposed along opposite lateral edges of the glass plate 13 as seen inFlG. ll. The thickness dimension of the spacers must conform to thetolerance requirement of the glass plate so that the combination of theglass plate and the adjacently disposed spacers present a uniformsupporting surface for a cylinder guide plate 22 which is positionedagainst the upper surface of glass plate id and the adjacentlypositioned spacers 2%.

As will be seen in H65. 1 and 2, the cylinder guide plate 22 is squarein shape and has its edges in alignment with the peripheral edges formedby the adjacently disposed glass plate i8 and spacers 20. Threecountersunk threaded boreholes 24 are formed along each. oppositelydisposed lateral edge portion of the guide plate 22. The aforementionedthreaded holes extend through the spacers 20 and the base plate 14.Thus, when suitable threaded fasteners areinserted through respectiveboreholes 2d, the vertically juxtaposed base plate M,

spacers 2t), and guide plate 22 are securely sealed together.

When replacement of glass 18 is required, these holddown fasteners areloosened thereby permitting the sliding of glass plate 18 from thecapper 110.

As will be seen by viewing FIGS. 1-4, the guide plate 22 includes acentral countersunk aperture 26 formed therein. The lowermost or inwarddiameter of the countersunk aperture is substantially the same as theouter diameter of cylinder 12 and the countersunk nature of the aperturepermits the rapid and accurate insertion of cylinder i2'within theaperture 26.

Molten capping material usually in the form of a combination of sulfurand tire clay is placed in cavity 26 of the capper and the hardenedconcrete cylinder 12, to be tested, is pressed against a channel iron 28which is vertically positioned to contact a longitudinal portion of thecylinder. The concrete cylinder is lowered into the molten cappingmaterial and allowed to remain in engagement with the glass plate iduntil the molten material hardens. The result is that the cylinder has acap formed on one end. The cylinder is then removed from the capper andthe other end of the cylinder is capped as just described. Again, whenthe molten capping material has hardened, the cylinder is removed fromthe capper and is now capped on both ends so that it may be tested in acompressiontesting machine for compressive strength.

in order to retain the length of cylinder 12 substantially perpendicularto the plane of glass plate ih, a channel iron 2% is verticallypositioned to contact a longitudinal portion of cylinder i2. The channeliron 28 is formed so that an inwardly tapering arcuate portion Ell alongthe lower portion of the channel iron permits the passage of a usershand between the channel iron and the test cylinder i2 during theinitial posi' tioning of the cylinder in the capper. The lowermost endof the channel iron 32 is suitably welded to the upper surface of guideplate 22.

The capped ends of the specimen permit full engagement between thespecimen and the bearing blocks of a conventional compression-testingmachine utilized to evaluate the strength of the specimen.

By utilizing the improved concrete cylinder capper of the presentinvention, rapid and inexpensive replacement of the capping plate 18,fabricated from glass, may be realized so that specimens may becontinually formed which conform with the tolerance requirements setforth by the standardized specifications.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes will bereadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

15 claim:

A concrete cylinder-capping device for use with a concrete cylinder, thecapping device comprising a base plate,

spacers positioned in mutually spaced relation on the plate, asubstantially planar capping plate removably positioned between thespacers and adapted to engage one end of the concrete cylinder, acylinder guide plate having an aperture therein, the guide plate beingretained in sealing engagement with the spacers and the capping plate toform a reservoir for capping material, and cylinder support means forcontacting a longitudinal portion of the cylinder thereby insuringsubstantial perpendicular retention of the cylinder with respect to thecapping plate.

2. The device set forth in claim 1 wherein the spacers include twoparallel spaced rectangular bars of uniform spacing dimension positionedin aligned underlying relationship with opposite lateral edges of theguide plate.

3. The device of claim 2 wherein the capping plate is fabricated fromglass and is positioned between the spacers in a manner permittingsliding removal of the glass plate from the device and subsequentreplacement thereof when desired.

4. The device set forth in claim 3 wherein the aperture in the cylinderguide plate is formed with a countersunk pen'phery tapering inwardlytoward the plane of the spacers.

S. The device set forth in claim 4 wherein the cylinder support meanscomprises a channel member fastened at one end thereof to the cylinderguide plate, the channel member having parallel-spaced flange portionsextending in parallelspaced relation to the axis of the guide plateaperture, the interior surface of the flanges providing means forcontacting a longitudinal portion of the cylinder.

1. A concrete cylinder-capping device for use with a concrete cylinder,the capping device comprising a base plate, spacers positioned inmutually spaced relation on the plate, a substantially planar cappingplate removably positioned between the spacers and adapted to engage oneend of the concrete cylinder, a cylinder guide plate having an aperturetherein, the guide plate being retained in sealing engagement with thespacers and the capping plate to form a reservoir for capping material,and cylinder support means for contacting a longitudinal portion of thecylinder thereby insuring substantial perpendicular retention of thecylinder with respect to the capping plate.
 2. The device set forth inclaim 1 wherein the spacers include two parallel spaced rectangular barsof uniform spacing dimension positioned in aligned underlyingrelationship with opposite lateral edges of the guide plate.
 3. Thedevice of claim 2 wherein the capping plate is fabricated from glass andis positioned between the spacers in a manner permitting sliding removalof the glass plate from the device and subsequent replacement thereofwhen desired.
 4. The device set forth in claim 3 wherein the aperture inthe cylinder guide plate is formed with a countersunk periphery taperinginwardly toward the plane of the spacers.
 5. The device set forth inclaim 4 wherein the cylinder support means comprises a channel memberfastened at one end thereof to the cylinder guide plate, the channelmember having parallel-spaced flange portions extending inparallel-spaced relation to the axis of the guide plate aperture, theinterior surface of the flanges providing means for contacting alongitudinal portion of the cylinder.